Chemical feeder



FIG. 1 is a front elevational view of a chemical feeder showing my new design, the broken line drawing of a hose line is for illustrative purposes only and forms no part of the claimed design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a chemical feeder, as shown and described. 